This application claims the priority of Korean Patent Application No. 2002-80826, filed on Dec. 17, 2002, in the Korean Intellectual Property Office, which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a channel allocation method, and more particularly, to a channel allocation method of channels having different transmission speeds in a wavelength division multiplexing (WDM) system.
2. Description of the Related Art
A plurality of methods have been used for a WDM system to prevent performance degradation due to a nonlinear effect. Examples of these methods include using a large dispersion fiber to reduce a walk-off length so as to reduce the interaction between channels, using a large effective core area fiber to reduce a nonlinear coefficient, and inducing the lowest optical power to a fiber to reduce a nonlinear effect due to optical power.
When a large number of channels over a wide band are used, a stimulated Raman scattering (SRS) effect among various nonlinear effects largely affects the transmission quality; however, the above-methods do not consider the effects of a Raman crosstalk according to the channel speed in the multirate WDM system.